Danger flocks get the bird

A bird dispersal system using GPS technology has been designed to more accurately track local bird activity around airports and on aircraft flightpaths.

A bird dispersal system using GPS technology has been designed to more accurately track local bird activity around airports and on aircraft flightpaths.

The device, called Ultima, disperses flocks by mimicking distress calls of individual species, and builds a database of the results for downloading to the airport analysis system for future reference.

Developed by Scarecrow Bio-Acoustic Systems of East Sussex, the system can be installed in any airport vehicle and consists of a computer, a GPS satellite navigation unit, a pair of loudspeakers and a touchscreen control interface for the operator.

The display information includes pictures of local bird varieties, controls to select the appropriate distress call and the ability to log the dispersal result by touching a screen menu. The entire record of activity can be transferred on a USB data stick to a PC for storage and analysis.

'The system is very graphically orientated, and there are images to aid identification of the birds,' said Tom Diamond, Ultima's developer. 'The order that the birds are displayed in propagates itself on its own database.' So when a user logs a successful bird dispersal, the system makes a note of its location, species call and pitch.

While earlier versions of these Scarecrow devices are used in more than 600 airports throughout the world, those involved in the airline business say that tackling the problem of bird strikes is still a major challenge because of a globally expanding bird population and the growth of airport traffic.

The Civil Aviation Authority reported 1,650 bird strike incidents in the UK in 2005. And according to the Central Science Laboratory's Bird Management Unit, bird strike collisions cost the world civil aviation industry around £610m a year and have resulted in the loss of 88 aircraft and 243 lives since 1912.

Most bird strikes happen near airports, and most countries have regulations requiring them to control risk on their property.

The system has its origins in an audiotape bird dispersal system used at Gatwick in the mid-1980s. Diamond said management scrapped them 'because they degraded, making them inefficient, and they confused the heck out of birds when the tape was stopped for rewinding.'

Gatwick directors noticed that digital audio emergency action messages, such as those on London's underground, did not seem to suffer from those problems, and so they called on that system's developer, Tony Walker, who later founded Scarecrow Bio-Acoustic Systems, to create a bird dispersal system for the airport.

As a result, a bio-acoustic system based on the same technology was developed and designated Digiscare. Walker enlisted the help of an ornithologist to refine the recordings using digital editing processes more normally associated with the music industry. During field trials, Walker discovered that birds reacted best to calls played from a natural start with minimal background noise.

'Why I say natural start, in other words the beginning of a sentence, is if I said to you "Day isn't it?" you wouldn't know what I was talking about,' explained Walker. 'But if I said, "Nice, day isn't it?" you would know immediately.

'Equally,' he added. 'if you play distress calls very loudly, the sound perceived by the bird is a novel sound, which they ignore.'

Walker said the user's manual tells operators to start the system with a pitch of zero and gradually increase it until birds take notice.

Diamond said that bio-acoustics do not disperse every type of bird. It usually only works with socially aggressive, flocking species. Ultima comes equipped with calls from 14 species of the airport's choice.

Seagulls are the most likely avian airport troublemaker, being responsible for an estimated 40 per cent of all bird strikes worldwide. A herring gull was to blame for the first fatal bird strike in 1912 when it became entangled in the control wires of a Wright Flyer, causing the plane to crash into the sea.

Diamond said the company's bio-acoustics system could have helped prevent such a gull-strike.

'We never say our system will save the day, or that it's the only system that works.' he said. 'But we do know what birds react best to it.'

Looking to the future, Diamond said the company and its clients are satisfied with their system's capabilities. He said that depending on industry demands, the system's software could be reconfigured to achieve more detailed dispersal results.

Other future improvements might include integrating the Ultima's GPS unit with the rest of the system's components to make the device more compact.